H&N: Thyroidectomy

Thyroidectomy or Hemithyroidectomy

Indications

Hemithyroidectomy is performed for diagnosis and resection of a possible thyroid malignancy in one thyroid lobe (see Thyroid Lumps). If malignancy is confirmed, a “completion thyroidectomy” may be carried out as a separate stage if the tumour is larger. It may also be performed for removal of a large unilateral benign nodule or cyst, if it is causing pressure symptoms or cosmetic issues.

Total thyroidectomy is performed for confirmed/very likely thyroid malignancy (except small malignancies), or to treat Graves’ disease which is not responding to medication. It may also be performed for a very large or retrosternal multinodular goitre causing pressure symptoms.

Procedure

A nerve monitor should be used to check integrity of the recurrent laryngeal nerve (RLN; see below). A horizontal incision is made in a skin crease overlying the thyroid gland. Subplatysmal flaps are raised, and the strap muscles divided vertically to expose the gland. The superior and inferior vascular pedicles are divided and the lobe is dissected out, taking care to identify and preserve the RLN and parathyroid glands. For hemithyroidectomy, the gland is divided at the isthmus.

Length of procedure

Variable, but usually 60-90 minutes per lobe.

Complications

Pain

Bleeding/haematoma A drain is used by some surgeons to prevent haematoma (see below).

Infection

Scar Usually quite good long-term cosmesis.

Need for further treatment Depending on histology.

Hypothyroidism Inevitable in total thyroidectomy; in hemithyroidectomy some patients may eventually require some T4 replacement.

Recurrent laryngeal nerve damage/palsy Hoarseness or weak voice. Long term palsy rates should be surgeon-specific, and are often around 2%. Temporary damage due to traction or heating is more common, and should improve. Even permanent injury may be compensated spontaneously over time, or may be treated with injection techniques. Rarely, bilateral RLN injury can lead to cord adduction and airway obstruction, necessitating urgent tracheostomy.

Hypocalcaemia Generally only a risk in total thyroidectomy. Damage to, or removal of, parathyroid gland(s) may cause a significant drop in serum calcium. This usually occurs in the first 24 hours post-operatively, so patients will usually have at least one calcium check during this time. Check the operation note or your local protocol for details. (See below for management).

Post-operative management

Patients usually stay overnight (sometimes two nights in total thyroidectomy).

Significant swelling at the operative site, usually quite soon after the procedure, indicates haematoma; this can cause airway obstruction due to laryngeal oedema. If haematoma is present, call your senior immediately. If the patient has any signs of respiratory difficulty, immediately remove the skin sutures at the bedside, open the wound, and evacuate haematoma or blood. Sit the patient up and give high-flow oxygen, fast-bleep an anaesthetist/crash team and call your senior.

For the above reason, a stitch cutter or staple remover should be close to hand at all times (eg taped to the wall behind the bed).

Calcium should be monitored postoperatively in all total thyroidectomies. The timing varies according to surgeon preference. If a patient becomes significantly hypocalcaemic, or symptomatic from hypocalcaemia, give IV calcium gluconate (infusion over 20-30 minutes with cardiac monitoring). Always discuss this with your senior and the medical/endocrine team. The patient may need to continue on oral calcium and vitamin D supplements, as may patients who have moderate hypocalcaemia.

Removal of sutures in 1 week at GP.

Clinic in 2-3 weeks for histology results.

TTO

Analgesia

Oral calcium/vitamin D if indicated

Total thyroidectomy: levothyroxine; dose as per local protocol. In some centres, liothyronine 20mg tds is used in cases of malignancy, but this is decreasing due to the use of recombinant TSH prior to radioactive iodine ablation.